Safety studies have shown that upwards of a 100,000 persons per year have been injured in accidents involving push type rotary power lawn mowers. While the utilization of a high speed rotating cutting blade positioned parallel to the ground and housed within a hollow mower deck or housing supported by front and rear wheels is a highly effective in cutting of grass, such mowers are extremely dangerous to operate, particularly since the mowers are often operated by children. The mower deck or housing is spaced somewhat above ground level by means of wheels which are in turn vertically adjustable so as to control the cutting height of the grass. Depending upon the height above the ground of the lower edge of the mower deck or housing, such mowers constitute a danger to the operator whether that be a child or an adult. Mowers follow the contour of the lawn, many lawns have portions which are on grade, and it is possible for the lawn mower to slip backwards, on a hill, while the blade is under powered operation. Under such circumstances it is possible for the operator to have the rotating blade cut into the operators foot due to an inadvertent backward movement of the mower. Additionally, as is often the case, objects such as toys or rocks, which are hidden in the grass, are in turn hit by the rotating blade and become projectiles which can fly in any given direction as a result of impact, often towards the operator.
Attempts have been made to provide safety shields for such lawn mowers. Shields have taken the form of inclined pivotable plates which are pivotably mounted to the rear vertical wall of the mower deck or housing or, alternatively, a roller may be pivotably mounted at its ends for rotation about its axis and in turn coupled to the mower deck. In such cases, the plate or roller is permitted to follow the contour of the lawn as well as to adjust for the height adjustment of the cut grass determined by variably adjusting the coupling between the rear wheels and the mower deck or housing.
U.S. Patents representative of the prior art safety shields in safety devices, are as follows:
U.S. Pat. No. 3,040,503 PA1 U.S. Pat. No. 3,106,812 PA1 U.S. Pat. No. 3,402,535 PA1 U.S. Pat. No. 3,461,653 PA1 U.S. Pat. No. 3,537,720 PA1 U.S. Pat. No. 3,555,793 PA1 U.S. Pat. No. 3,570,225 PA1 U.S. Pat. No. 4,216,643
It may be appreciated that some of the prior art devices are simple, others complicated. Some permit latching of the safety shield in a raised or out of ground contact position when the mower is out of use. Some provide for height adjustment to vary the height of the roller relative to the deck or housing or, alternatively, to limit the movement of the safety device whether it be a plate or roller relative to the mower deck or housing.
It is an object of this invention to provide a safety roller assembly for bracket mounting to a rotary lawn mower deck which is of relatively few parts, which is simple, light and inexpensive and which may be mounted to either of the mower deck top or the vertical mower deck rear wall and in which vertical travel of the roller is limited and carefully controlled by the mechanism for mounting the roller to the mower deck.
Other objects and a fuller understanding of the invention may be had by referring to the following description and claims.